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41.
盆地的形成和充填过程模拟──以拉伸盆地为例 总被引:18,自引:1,他引:17
沉积盆地定量动力学模拟和分析是目前地学领域的一个研究热点。文中建立的拉伸盆地模拟系统可模拟拉伸盆地的沉降过程、估算盆地的拉伸量、分析盆地深部结构和热流背景;动态模拟盆地的充填过程及预测层序格架和沉积体系域的分布样式。沉降和热史模拟结合了二维的回剥法和简单或纯剪切的盆地形成模型。盆地充填模型综合考虑了盆地的构造沉降、均衡作用。沉积物供给。海(湖)平面变化等对盆地充填过程的控制作用。对莺、琼盆地模拟分析揭示了盆地的幕式拉伸过程和深部热演化;层序模拟提示了盆地沉降。海平面变化等对盆地充填演化的控制作用。 相似文献
42.
Floodplain wetlands are dynamic systems undergoing frequent hydro-sedimentological changes. Tropical/subtropical wetlands have even more pronounced climatic and biological influences on the sediment dynamics. In the current study, a protected subtropical wetland in Bihar(India) has been assessed for its sedimentary and mineralogical status. Sediment characteristics and associated granulometric parameters are discussed to highlight the wetland’s hydrogeomorphic character, energy dimension, and th... 相似文献
43.
考虑到多维地震输入对网架结构的不利影响,基于形状记忆合金超弹性,研制出一种兼具自复位、高耗能及放大功能于一体的形状记忆合金复合黏滞阻尼器(Hybrid Shape Memory Alloy Viscous Dampers,简称HSMAVD),并通过试验研究该阻尼器在循环荷载作用下的力学性能;然后以平面四角锥网架模型为基础,将该阻尼器替换部分网架结构杆件,并分析该阻尼器减震控制效果。结果表明形状记忆合金与黏滞阻尼器复合后具有良好的协同工作能力,可有效发挥形状记忆合金的超弹性和黏滞阻尼器的速度相关特性,使其具有稳定的滞回性能和良好的耗能能力;采用阻尼杆件替换原杆件的方法既能对结构进行有效的减震控制,又不改变原有的结构形式,是一种优越的减震控制方法,并为HSMAVD被动控制系统在结构抗震中的实际应用提供新思路。 相似文献
44.
The paper describes the distinctive features of the pseudo‐dynamic test method as implemented at the ELSA reaction‐wall facility. Both hardware and software aspects are considered. Particular attention is devoted to the digital control system and to a coupled numerical–experimental substructuring technique allowing realistic earthquake testing of very large structures. Mathematical and implementation details corresponding to this testing technique are given for both synchronous and asynchronous input motion. Selected test results illustrate the advantages of the presented features. Copyright © 2000 John Wiley & Sons, Ltd. 相似文献
45.
Ahmet Güllü Ercan Yüksel Cem Yalçın A. Anıl Dindar Hasan Özkaynak Oral Büyüköztürk 《地震工程与结构动力学》2019,48(1):27-45
Input energy is the principal component of the energy balance equation. It is beneficial to determine, through its components, how the recoverable and irrecoverable energies are distributed within the structural elements. Several equations and attenuation relations to define mass-normalized input energy spectra exist in the literature. They are mainly proposed for elastic systems subjected to far-fault EQs. There is a lack of experimental verification of these proposed spectra. In this paper, experimental assessment was performed to the existing spectra, and further improvements were accomplished. For this purpose, steel cantilever columns were tested on the shake table for two specific historical EQs coincidently having similar spectral acceleration values. Based on the experimental results, a three-part mass-normalized relative input energy spectrum was formulated including soil type, EQ (corner period, intensity, duration, spectral acceleration, and velocity), and structural behavioral characteristics (period and structural damping). The proposed input energy spectrum was experimentally calibrated and numerically validated for various EQs featuring near- and far-field types. Analytical and experimental comparisons were made between the previously developed spectrum and the newly proposed one. The validation studies and the statistical evaluations exposed that the proposed spectrum yielded better agreement with the experimental and numerical results. 相似文献
46.
A series of studies was conducted on three buildings of steel reinforced concrete structures with RC shear walls damaged in the 1995 Hyogo-ken Nanbu earthquake. These buildings are located in an area where structural damage centred around. Two of these buildings suffered severe damage, while the third was not structurally damaged. Our studies deal with site inspections, including micro-tremor measurement of buildings, the evaluation of input motions, and the response analyses considering soil–structure interaction. The results of simulation analyses of the two severely damaged buildings correspond to their actual damage state. From the response analyses of the one slender building with no structural damage, it was concluded that uplifting is the main reason it did not suffer any structural damage. Through these studies, the importance of soil–structure interaction and effective input motion is fully understood. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
47.
本文对白令海北部陆坡B2-9站位沉积物岩芯开展了高分辨率的生物标志物分析,获得了研究区近一万年来陆源长链正构烷烃(简写为烷烃)的输入及其源区植被结构的变化等相关记录。结果表明,nC27是烷烃中最高的主碳峰,对烷烃总量的贡献也最大,这可能与源区木本植物的丰度及其分布有关;nC23的含量也较高,可能主要是来源于北半球沿海地区广泛分布的一类沉水植物。全新世期间,烷烃总量分别在7.8 ka B.P.,6.7 ka B.P.和5.4 ka B.P.经历了三次阶梯状的下降过程,呈现出四个相对稳定的阶段,可能主要受控于早全新世海平面上升以及源区气候环境和植被分布的变化。烷烃的分子组合特征各参数(如CPI、ACL以及nC31/nC27等)的变化则表明,烷烃主要来自陆生高等植物,且全新世期间植被结构较为稳定,木本植物占据优势。此外,在几个较短的时期内,烷烃总量及其分子组合特征等参数的变化具有同步性,表明在这些时期特殊的气候条件下,源区木本植物烷烃对烷烃总量的贡献率的增加可能低于草本植物烷烃和化石烷烃。 相似文献
48.
Influencing mechanism of energy-related carbon emissions in Xinjiang based on the input-output and structural decomposition analysis 总被引:1,自引:1,他引:0
Analysis of carbon emission mechanism based on regional perspectives is an important research method capable of achieving energy savings and emission reductions. Xinjiang, an important Chinese energy production base, is currently going through a period of strategic opportunities for rapid development. Ensuring stable socio-economic development while achieving energy savings and meeting emission reductions targets, is the key issue currently facing the region. This paper is based on the input-output theory, and conducts a structural decomposition analysis on the factors affecting energy-related carbon emissions in Xinjiang from 1997 to 2007; this analysis employs a hybrid input-output analysis framework of “energy - economy - carbon emissions”. (1) Xinjiang’s carbon emissions from energy consumption increased from 20.70 million tons in 1997 to 40.34 million tons in 2007; carbon emissions growth was mainly concentrated in the production and processing of energy resources, the mining of mineral resources, and the processing industry. (2) The analysis of the direct effects of the influencing factors on carbon emissions showed that the change in per capita GDP, the final demand structure, the population scale, and the production structure were the important factors causing an increase in carbon emissions, while the decrease in carbon emission intensity during this period was the important influencing factor in stopping the growth of carbon emissions. This showed that while the sizes of Xinjiang’s economy and population were growing, the economic structure had not been effectively optimized and the production technology had not been efficiently improved, resulting in a rapid growth of carbon emissions from energy consumption. (3) The analysis of the indirect effects of the influencing factors of carbon emission showed that the inter-provincial export, fixed capital formation, and the consumption by urban residents had significant influence on the changes in carbon emissions from energy consumption in Xinjiang. (4) The growth of investments in fixed assets of carbon intensive industry sectors, in addition to the growth of inter-provincial exports of energy resource products, makes the transfer effect of inter-provincial “embodied carbon” very significant. 相似文献
49.
利用中国30个省区2002-2012年R&D投入和城镇化水平的面板数据,通过单位根检验、协整性检验和面板数据模型,探讨中国R&D投入对地区城镇化发展水平的影响。结果表明:①中国各省区城镇化水平与R&D投入存在长期稳定关系,但城镇化水平的科技支撑基础仍处于较低水平,并且不同省区的R&D投入产出存在较大差异。②总体上看来,R&D人员投入产出弹性高于R&D经费投入,说明城镇化对R&D人员投入的依赖性更大。③R&D投入对城镇化的作用与其所处的城镇化阶段有关,同时,R&D投入与城镇化的协调度也是影响R&D投入产出的关键因素。④误差修正模型结果表明,R&D短期投入对城镇化的影响存在一定的滞后效应。 相似文献
50.